An optical time-of-flight distance measuring device comprises a transmitter (102) and a receiver (105). The transmitter (102) comprises a semiconductor laser (200) for outputting optical pulses (110, 110') of controllably variable temporal widths. The semiconductor laser (200) operates in an enhanced switching regime for the optical pulses of a minimum generable temporal width of the laser (200). The receiver (105) comprises a matrix (300) of single photon avalanche detector elements (310 to 326) of a Geiger mode, a receiver controller (302), and one or more time-to-digital converters (330). The single photon avalanche detector elements (310 to 326) detect optical pulses reflected from the target (112) to the matrix (300), and each of the single photon avalanche detector element (310 to 326) outputs an electric signal in response to each detection. A number of the time-to-digital converters (330) is smaller than a number of the single photon avalanche detector elements (310 to 326) of the matrix (300). The receiver controller (302) connects at least two of the single photon avalanche detector elements (310 to 326) with different time-to-digital converters (330). The time-to-digital converters (330) connected with the single photon avalanche detector elements (310 to 326) provide timings of detected optical pulses on the basis of each output electrical signal for determination of information associated with a distance of the target (112).